Using optical fibers to convey light from a source to a destination presents a number of handling challenges. First they are manufactured with specialized coatings on both the input and output end face so the optical fiber can't be cut to length at installation. Second, the optical fibers minimum bend radius must be protected: in other words, if the optical fiber is bent tighter than approximately 200 times its cladding diameter it could be damaged. The combination of these two limitations makes optical fiber routing difficult. The difficulty of managing extra optical fiber length is increased by optical fiber length manufacturing tolerance: for example, optical fibers are not manufactured to an accurate length so the amount of extra optical fiber length varies from one installation to the next.